Fuel Cell Works Supplemental News Page

**Japan's CRIEPI develops all-ceramic Solid Oxide Fuel Cell**
Publication date: 25-April-2004 Source:Asia Pulse Pte Ltd
The Central Research Institute of the Electric Power Industry (CRIEPI) has developed a fuel cell made entirely of ceramic materials. Because ceramics can withstand higher temperatures than metals can, the use of them for the plates that connect individual cells enables the entire fuel cell to operate at a higher temperature, generating electricity with greater efficiency. The new product is a type of solid oxide fuel cell. The individual cells in such a cell are typically connected by plates of metals such as nickel that are easy to process. The disadvantage of metal plates is that they oxidize at high temperatures and deteriorate, so the fuel cell must be run at temperatures of only around 700-800 C, sacrificing some of the potential output of the fuel cell. Ceramic connectors have not been used until now because they also tend to chemically react and deteriorate, creating the risk of hydrogen and air leaks . CRIEPI solved this problem by adding a calcium-based inorganic oxide material to the ceramic to inhibit the chemical reactions that would otherwise lead to deterioration. The result is an all-ceramic cell that can operate at a temperature of 1000 C and generate 1 watt per square centimeter of electrolyte, which is five times as much as a conventional cell of its type can manage. Moreover, the new fuel cell can operate for 2,000 continuous hours, a 50-fold increase, because cracking due to the different thermal expansion coefficients of metals and ceramics is not a factor. ~

The Central Research Institute of the Electric Power Industry (CRIEPI) has developed a fuel cell made entirely of ceramic materials.

Because ceramics can withstand higher temperatures than metals can, the use of them for the plates that connect individual cells enables the entire fuel cell to operate at a higher temperature, generating electricity with greater efficiency.

The new product is a type of solid oxide fuel cell. The individual cells in such a cell are typically connected by plates of metals such as nickel that are easy to process. The disadvantage of metal plates is that they oxidize at high temperatures and deteriorate, so the fuel cell must be run at temperatures of only around 700-800 C, sacrificing some of the potential output of the fuel cell.

Ceramic connectors have not been used until now because they also tend to chemically react and deteriorate, creating the risk of hydrogen and air leaks .

CRIEPI solved this problem by adding a calcium-based inorganic oxide material to the ceramic to inhibit the chemical reactions that would otherwise lead to deterioration.

The result is an all-ceramic cell that can operate at a temperature of 1000 C and generate 1 watt per square centimeter of electrolyte, which is five times as much as a conventional cell of its type can manage. Moreover, the new fuel cell can operate for 2,000 continuous hours, a 50-fold increase, because cracking due to the different thermal expansion coefficients of metals and ceramics is not a factor.